Ventilating device



1952 K. M. GANGER ETAL 2,622,793

VENTILATING DEVICE Filed June 11, 1947 zsusms snmm 2 25 mmmnmumu W1 r muwuwy 7 3 1143;? BY 6W; 6. MM WZJKQM ATTORNEYS Patented Dec. 23, 1952 UNITED STATES PATENT OFFICE VENTILATING DEVICE Karl M. Ganger and John B. Burrowes, Dayton, Ohio, 'assignors to The Lau Blower Company, Dayton, Ohio, a corporation of Ohio Application June 11, 1947, Serial No. 753,886

4 Claims.

Thisi-nvention relates to ventilating fans.

One of the principal objects of the invention is to provide a portable ventilating fan of simple and strong construction wherein the air stream created by the fan blades is so directed and controlled as to promote effective cooling of the fan motor for increased effiicency in use.

Another object is to provide a ventilating .fan wherein the fan blades and the mounting for the motor are arranged in cooperative relation to direct a portion of the main air stream through the motor to provide a cooling effect thereon in operation.

It is also an object of the invention to provide a hub and spider for mounting fan blades .on a fan shaft which includes supplemental blades constructed and arranged to draw a-cooling flow of air through the motor and then to direct this air into the main air flow of the fan.

A further object is to provide a ventilating fan including a motor and having main fan blades for creating a main ai-r flow exteriorly of the motor and supplemental fan blades arranged to create a radially outward air flow at a position in front of the motor such that air is drawn through the motor for cooling action and then caused to join the main air flow. a

Other objects and advantages of the invention will be apparent from the following description, the accompanying drawing. and the appended claims.

This application is a continuation-in-part of our application Serial No. 733,494, new Patent No. 2,453,009, filed March .10, 1947.

In the drawings, in which like characters of reference designate like parts throughout Fig. 1 is a view in perspective of the front of a ventilating fan constructed in accordance with the present invention;

Fig. 2 is a view in perspective of the back of the fan shown in Fig. 1;

Fig. 3 is .a view in side elevation of the fan shown in Fig. 1;

Fig. 4 is a View in horizontal section taken substantially on the line 4-4 of Fig. 3;

Fig. 5 is an enlarged fragmentary view of the back of the fan, with parts broken away to show details of internal construction and arrangement;

Fig. 6 is a somewhat digrammatic view taken approximately in section on the line 6-6 of Fig. .5;

Fig. 7 is a fragmentary view taken approximately on the line 'l| of Fig. 6 and Figs. 8 and 9 are diag ammatic views in perspective illustrating the use of the fan when suspended in different angular positions.

Referring to the drawing, which illustrates a preferred embodiment of the present invention, the main frame for the fan is shown as a sheet metal panel ill of rectangular shape having a large circular opening H through the center thereof. The metal surrounding this opening it is curved forwardly to form a flange 12 constituting a control ring for the fan, and panel 1 ii is also bent rearwardly along its edges to provide a rearwardly extending peripheral flange It. A relatively narrow supplemental panel [5 or back strip has its ends curved forwardly at 16 and secured, as by welding, to the inner surface of flange I3 at opposite sides of main panel It, thus positioning the main part of this supplemental panel in spaced parallel relation with the main panel and overlying the center of the opening 'H Also, the supplemental pan-e1 is formed with an outwardly projecting rib 11 for increasing its rigidity.

An electric motor 20 is mounted in cantilevered fashion on the supplemental panel 5, and it extends with its drive shaft 2| substantially centrally through the opening I l in the main panel. As best seen in Figs 4 to 6., the mounting for this motor includes a bracket comprising a plate 22 of relatively stiiT sheet metal to which the motor is removably secured as by means of the nuts and bolts 23. This mounting plate is of substantially the same height as the supplemental panel l5, and it extends substantially across the straight portion of panel i 5 and has its ends 24 flanged as shown in Fig. 4 for attachment to the panel is as by means of nuts and bolts 25. This cons-truction provides for supporting the weight of the motor at spaced points on panel [5 so located that its curved portions I 6 have a bracing action against twisting of the panel under the angular force imparted by the Weight of the motor, and the flanged ends 24 of plate 22 provide for offsetting the plate from panel l5, as shownin Figs. 4 to 6, to accommodate the outer ends of the mounting nuts and bolts 23 for the motor.

The mounting bracket for the motor also includes means for diverting and directing a part of the main air flow of the fan through the motor 20 to provide a cooling effect thereon. Referring to Figs. 4 to 6, it will be seen that the top and bottom edges of bracket plate 2 2 are formed as flanges 26 arranged to extend upwardly and downwardly. respectively, from plate-22 and at an acute anglethereto, for example an angle of the order of 30. With the plate 22 and panel i5 of substantially the same height as stated, the flanges 26 will extend beyond the upper and lower edges of panel 15, as shown in Fig. 6, and they will thus act as scoops or bafiies to divert a portion of the main air flow into the space between bracket plate 22 and panel l5, as indicated by the arrows 21 in Fig. 6. Accordingly and referring particularly to Fig. 5, the plate 22 is provided with a plurality of spaced holes 28 arranged opposite the end of motor '29 and substantially in line with the inlet holes 29 for air in the rear end of the motor, these holes 28 and 29 thus cooperating to conduct into the motor the supplemental air flow diverted by flanges 26 from the main air flow through the fan.

The blade portions of the fan include both main fan blades for creating a main air flow through the opening II in central panel I9 and also supplemental blades for drawing the supplemental air flow diverted by flanges 26 through the motor and thereafter causing this supplemental air flow to rejoin the main air flow. Referring first to Fig. 4, it will be seen that the motor 29 and its shaft 2| project through the opening I I and beyond the plane of the main panel ID. A hub 39 is secured to the shaft 2|, and it is formed to mount the main fan blades in proper position in the plane of main panel I9 to draw air through opening ll.

Referring to Figs. 6 and 7, the hub 39 carries at its rearward end a spider 3|, which is welded, staked or otherwise secured to the hub. The spider 3| includes three generally radially extending arms or fins which are bent to provide portions 32 extending rearwardly and overlapping the motor 20, and these arm portions 32 are further bent or formed in a reverse direction to provide radially extending portions 34 to which the main fan blades 33 are riveted or otherwise secured as shown in Figs. to 7. The arm portions 34 may also be formed at an oblique angle with respect to the axis of shaft 2|, as shown in Fig. 6, to provide the desired angular positioning of the fan blades 33 with respect to the shaft axis. It will thus be seen that this hub and spider construction provide for a maximum required depth of the fan as a whole from front to back equal to not substantially more than the axial length of the motor 20 plus a shaft 2| of suflicient length to support the hub 30, while at the same time providing for mounting the main fan blades 33 directly within the central opening ll of the main panel 19 and substantially in the plane of this panel and the control ring l2 in proper position to create the desired main air flow passing externally of motor 29 and through opening I l as indicated by the arrows 35 in Fig. 6.

The spider 31 also carries supplemental fan blades arranged to draw through motor 20 the supplemental air flow diverted from the main air flow by flanges 26 and thereafter to cause this supplemental air flow to rejoin the main air flow. Referring to Figs. 6 and 7, an initially circular disk 36 is welded or otherwise secured to the rearward side of spider 3|, i. e. between the spider and motor 20. This disk is somewhat smaller in radius than the spider, and it is formed to provide a plurality of radially arranged supplemental fan blades 31 extending rearwardly from the spider. As shown in Figs. 6 and 7, each of these blades 31 is formed by severing a tab portion 31 from the body of the disk along two sides and bending the tab along its third side into a position substantially at right angles to the plane of the disk, this third. side of each tab 4 being controlled to lie substantially radially of the disk as shown in Fig. '7.

It will be seen that with this construction, when the spider 3| is rotated, the supplemental fan blades 31 will create a centrifugal flow of air in the space directly behind the spider, as indicated by the arrows 38 in Fig. 6. This in turn will act to draw through the motor 26 the supplemental air flow diverted by flanges 26, as indicated-by the dotted arrows 39 in Fig. 6. Thus to consider the air flow pattern through the fan as a whole, the main fan blades 33 will create a main air flow through the opening II in main panel H) as indicated by arrows 35, and this main air flow will pass externally of the motor 26. The flanges 26 will divert a portion of this main flow, as indicated by arrows 21, into the space between bracket plate 22 and supplemental panel l5. This action of the flanges 26 will be aided by the centrifugal air flow created by the supplemental fan blades 31, which is effective to draw the resulting supplemental air flow through motor 20, as indicated by the dotted arrows 39 in Fig. 6, and thus to cool the motor. After passing through the motor, the supplemental air flow is directed radially outwardly by the action of the supplemental fan blades, as indicated by arrows 38 in Fig. 6, and thus rejoins the main air flow.

Protective screens are provided at both the back and front of the fan. Referring particularly to Figs. 2 to 4, the screen 49 at the back of the fan is shown as formed in two parts from a relatively closemesh screening such as sheet metal grillwork. These two grills have their edges secured, as by welding, to the inner surfaces of flange I3 and supplemental panel 15, and they thus aid in bracing the supplemental and main panels relative to each other to provide further support for the weight of motor 20. The corners of screen 40 are curved, as shown particularly in Fig. 2, both for purposes of strength and to provide a rounded and pleasing appearance, and means are also provided for protecting these corners in transportation or use. Referring to Figs. 2 and 3, protective ribs 42 each have one end secured as by welding to the corners of flange l3 on the main panel 10, and these ribs are curved to overlie the corners of screen 40, with their outer ends free as shown in Fig. 2. These ribs thus serve to brace the corners of screen 40 and also to shield them in transportation and use.

The screen 44 at the front of the fan is shown as a relatively open-mesh 'wire screen having a rectangular outer rim 45 which is removably mounted at the front of main panel [0 by means such as the screw clamps 46. The remainder of screen 44 is curved forwardly and inwardly from itsrim 45 to overlie the center of the fan and to shield the blades from coming into contact with any person or object in use, and as shown in Fig. 4, the middle portion of this screen ,is spaced from the supplemental panel I 5 and back screen 49 by only slightly more than theaxial length of motor 29 and its shaft 2|, thus further contributing to the compactness of the fan. Also, the use of removable clamps 46 for mounting screen 44 facilitates its ready removal for replacement or servicing of the motor 29 or any of its associated or component parts.

Means are provided for supporting the fan for operation in an upright position, and these sup porting means also serve to provide additional bracing for the main framework. Referring particularly to Figs. 2 and 3, the supporting means are shown as :a pair of brackets or legs each including a horizontal portionill .and a portion ail extending upwardly from the rearward end of the horizontal portion 59. This upwardly extending portion of each leg is secured to the supplemental panel 15, as by means ofone of the bolts .25 which connect the supplemental panel and the mounting plate 122 for the motor. and the horizontal leg portions :50 are similarly secured to the main panel I'D, as by bolting to its peripheral flange l3, thus providing additional braces between the main and supplemental panels to support the weight and vibration of the motor and fan blades. .As' shown in Fig. 3, the horizontal leg portions 50 extend from a position forward of the plane of main panel ID to a position spaced rearwardly beyond the plane of supplemental panel l5, to provide an elongated supporting base adapted to rest upon a suitable horizontal surface, and. the opposite ends of leg portions 50 may also be equipped with suitable feet such as rubber grommets 5.2 as shown in Fig. 3. This construction provides for supporting the fan in well balanced upright position for operation, with the rearward feet 52 spaced sufficiently behind the plane of blades 33 to support the angular thrust on the fan in use and prevent its overtipping.

A control switch is mounted on the fan in a convenient but relatively inconspicuous position. A switch. box 55 is shown as mounted at the back of main panel l0 and adjacent one corner, where it will be substantially concealed by flange i3 and the rear screen 40. The wires 56 from this switch to motor 20 are readily concealed by flange I3 and supplemental panel [5, and they may be passed through suitable holes in the bracket plate 22 and its flanged ends 24 as shown in Figs. 4 and 5. The operating shaft for the switch is extended through the main panel ID to a switch lever 57 conveniently located at the front of the main panel [0, and an electric cord 58 for transmitting current to the switch may be brought out through the mesh of screen 40 for attachment in a suitable wall socket or like outlet fixture.

This fan may also be used in suspended position, instead of being mounted on a supporting surface, and this is often desirable particularly to provide for directing the air stream at an angle to the horizontal. For such uses, the fan may readily be suspended by means such as chains attached to the front or back screens, and the construction of the fan as described and shown in Figs. 1 to 4 provides for such location of the center of gravity, that when the fan is suspended, it will automatically tilt forward or backward, depending upon whether the suspending means are attached to the back or front screen, respectively. Such suspended mountings are shown in Figs. 8 and 9.

Referring to Fig. 8, a fan constructed as described in connection with Figs. 1 to 4 is indicated generally at 60 as suspended in front of a window SI and facing inwardly. The suspending means for the fan are shown as a pair of chains 62 each having one end attached to the adjacent side of the window frame and the opposite end attached to the back screen of the fan, for example by means of hooks 63 which are readily attached to the screen. Fig. 9 shows a similar mounting of the fan in which the chains 62 are attached to the front screen of the fan.

As shown in Fig. 8, when the suspending chains are attached to the back screen, the fan hangs .6 in a forwardly tilted position, thus providing for directing the air flow into the room at a downwardly inclined angle. In the position .shown .in Fig. 9., the fan tilts backward and thus directs the air flow upwardly into the room. If the fan is turned to face the window, the air flow will be similarly angularly directed towards and out through the window.

While the form of apparatus herein described constitutes a preferred embodiment of the invention, it is to be understood that the invention is not limited to this precise form of apparatus, and that changes may be made therein without departing from the scope {of the invention which is defined in the appended claims.

What is claimed is:

"1. A portable ventilating fan of the character described comprising a main panel having a central opening, a supplemental panel overlying said opening and secured to said .main panel in rearwardl-y spaced and parallel relation, 9. motor having a motor shaft, fan blades carried by said shaft, bracket means mounting the rearward end of said motor on said supplemental panel to support .said motor in cantilevered fashion with said fan blades .in position to create a main air flow passing forwardly through said opening externally of said motor, said bracket means including a portion projecting into the path of said main air flow to divert a portion of said main air flow to form a supplemental .air flow directed towards said motor, and supplemental fan blades carried by said shaft and spaced axially forwardly of said main fan blades in position to draw said supplemental air flow through said motor to cool said motor and thereafter to direct said supplemental air flow radially outwardly into said main air flow.

2. A portable ventilating fan of the character described comprising a main panel having a central opening, a motor having a motor shaft at the forward end thereof, hub means on said shaft including portions extending rearwardly in overlapping relation with said motor, fan blades secured to said hub portions and extending rearwardly therefrom beyond the forward end of said motor and in close radial relation therewith to create a main air flow passing closely along the outside of said motor, means forming a cantilevered mounting for the rearward end of said motor to support said motor rearwardly of said main panel with said fan blades in position to direct said main air flow forwardly through said opening, said motor having openings at either end thereof defining ventilation passages therethough, bafile means on said motor mounting and rearwardly of said motor for diverting part of said main air flow to form a supplemental air flow, and means for directing said supplemental air flow through said ventilation passages to cool said motor and thereafter to rejoin said main air flow.

3. A portable ventilating fan of the character described comprising a main panel having a central opening, a relatively narrow supplemental panel overlying said opening, means securing said supplemental panel to said main panel in rearwardly spaced and parallel relation with said main panel, a motor having a motor shaft at the forward end thereof, a plurality of fan blades, hub means supporting said fan blades on said shaft with said blades extending rearwardly beyond the forward end of said motor and in close radial relation therewith to create a main air flow passing closely along the outside of said motor,

means forming a cantilevered mounting for the rearward end of said motor on said supplemental panel to support the forward end of said motor with said fan blades positioned to direct said main air flow forwardly through said opening, said motor having ventilation passages extending lengthwise therethrough, and said mounting means including a projecting portion rearwardly of said motor forming a scoop for diverting a portion of said main air flow to form a supplemental air flow and for directing said supplemental air flow through said ventilation passages to cool said motor.

4. A portable ventilating fan of the character described comprising a main panel having a central opening, a relatively narrow supplemental panel secured to said main panel and extending rearwardly of and in parallel relation with said main panel at a position located opposite the center of said opening, a motor having'a motor shaft at the forward end, thereof, a plurality of fan blades supported on said shaft in close radial relation with said motor to form a main air flow passing closely along the outside of said motor, a bracket plate of substantially the same Width as said supplemental panel secured tothe rearward end of said motor, means securing said bracket plate to said supplemental panel and in forwardly spaced relation therewith to form a cantilevered mounting for said motor supporting the forward end thereof with said fan blades in position to direct said main air flow forwardly through said opening, said motor having ventila- 1 REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 991,367 Primley, et a1 May 2, 1911 1,383,883 Truitt, et a1. July 5, 1921 1,620,875 Currie Mar. 15, 1927 1,939,399 Larsh Dec. 12, 1933 1,982,537 Rathel Nov. 27, 1934 1,991,194 Child Feb. 12, 1935 2,098,407 Smith Nov. 9, 1937 2,130,802 Kisling Sept. 20, 1938 2,130,910 Smith Sept. 20, 1938 2,262,695 Moeller Nov. 11, 1941 2,397,171 Troller, et al Mar. 26, 1946 

